corrado venturini, as per h20564.www2.hp.com/hpsc/swd/public/readIndex?sp4ts.oid=6732463&swLangOid=8&swEnvOid=4158 an update to your computer's buggy and outdated BIOS is available (F.39). If you update to this following https://help.ubuntu.com/community/BIOSUpdate does it change anything?

If it doesn't, could you please both specify what happened, and provide the output of the following terminal command:
sudo dmidecode -s bios-version && sudo dmidecode -s bios-release-date